package com.check.operation.util;

public class StringUtils {
	
	public static final String INTEGER = "^-?[1-9]\\d*$";
	
	private StringUtils() {}

	public static boolean isNull(String s) {
		return s == null || "".equals(s);
	}
	
	
	public static boolean isNotNull(String s) {
		return !isNull(s);
	}


	public static boolean isBlank(CharSequence cs) {
		int strLen;
		if (cs != null && (strLen = cs.length()) != 0) {
			for(int i = 0; i < strLen; ++i) {
				if (!Character.isWhitespace(cs.charAt(i))) {
					return false;
				}
			}
			return true;
		} else {
			return true;
		}
	}

	public static boolean isNotBlank(CharSequence cs) {return !isBlank(cs);}
}
